I don't have that printer, nor do I have experience with wireless printers,
but two observations:

-- many printers are supported naively, built into the Linux kernel

-- look up "Linux printers" and you may find the information you are looking
for there

Have a look at http://localhost:631/ and www.cups.org

CUPS=Common Unix Printing System which shows all printers working with Unix
type systems including Linux.
Sofar I have found all the printers 'thrown at me' in CUPS and they all work
with Linux from HP Laserjet (SCISI) to Epson 440 and R285 (USB)

The main problem you will find is that print servers do just that,
i.e. share the printing function. It's more than possible that the
scanning function of your DX7400 won't be available over the network.

You'd probably be as well just getting a wireless multi-function
device and using that. Certainly would be less hassle setting it up !

I'm pretty sure you don't need a driver for the print server, just for the
printer. Since you already have the printer, I assume it has been working for
you.

I have a Brother laser printer which can be used wirelessly, but I chose to
cable it to my router. Every computer in the house can use it.